Rotary blower casing



Oct. 29, 1935. v V J AVERY ROTARY I BLOWER CASING Filed April 15, 1933 3 Sheets-Sheet l OCt. 29, J AVERY ROTARY BLOWER CASING Filed April 15, 1935 3 Sheets-Sheet 2 w mom/W t. 29, 1935. A ERY 2,018,827

ROTARY BLOWER CASING Filed April 15, 19:53 5 Shets-Sheet 5 Patented Oct. 29, 1935 onus- ROTARY BLOWER CASING John Avery, Wauwatosa, Wis., assignor to Allis- Chalmers Manufacturing Company, Milwaukee, Wis., a corporation of Delaware Application April 15, 1933, Serial No. 666,257

9 Claims.

This invention relates to improvements in rotary blowers, compressors, fans or pumps and more particularly to an improved and simplified construction of the casing and stationary portions of centrifugal blowers, compressors, fans or pumps constructed principally of sheet metal and having an impeller or impellers mounted on a shaft supported between two bearings.

, In such constructions heretofore, the bearing pedestals have been generally separated entirely from the casing, necessitating alinement of pedestals and casing on a baseplate or on the ultimate foundations and requiring separatefeet on the blower casing; or the pedestals have been bolted or otherwise secured directly to the casing, forming the supports for same, but requiring numerous internal stiffening members in order to provide sufiicient rigidity; or the bearing housings have been secured to the casing and literally hung upon it, the connection to the baseplate or foundation being made only through feet on the casing, thus allowing the bearings to move with movement of the casing, "andogiving rise topossibility of misalinements.

An object of the present invention is to provide a sheet metal rotary blower or compressor structure in which the internal stationary pertions and the bearings therefor are supported.

independently of the casing.

Another object of the present invention is to provide a rotary blower or compressor structure in Which the casing. the internal stationary poi:

tions and the bearings are severallymountedon common supporting members resting directiy on the foundation.

Another object of the present invention is to providean improved simplified construction in a sheet metal rotary device having the requisite rigidity while supporting the bearings independently of the casing, providing a common support for bearings and casing in'siich' a manner as to'make a baseplate unnecessary, eliminating numerous" internal stiffening members, and eliminating parts heretofore necessary by provid in the construction, three steel plates to fulfill the'combined functions of supporting the bearings; supporting the casing, acting as internal stiffening members, defining the inletpassage to'the blower, compressor, fan or pump and form-' ing afguiding vane in theinlet passage.

Objects and advantages, other than those above set forth, will beapparent from the following description when read in connection with the accompanying. drawings in which:!

Fig. "1 is I a vertical cross-section taken on. a

substantially central plane of a single stage double intake blower of the centrifugal type;

Fig. 2 is a side elevation on a reduced scalev of. the embodiment illustrated in Fig. 1 and in which drawing;

Fig. 3 is an elevation, on the scale of Fig. 2, of one of the endplates forming a portion of the inlet passageways and the supporting structure of the blower; and m Fig. 4 is a vertical cross-section taken on a. substantiallycentral plane of ,a two" stage single intake blower of the centrifugal type.

Referring more particularly to the drawings by characters of reference, the blower illustrated in Figs. 1 and2 is provided with a shaft driven by any, suitable prime mover (notshow-n) and carr'yin'gj an impeller wheel I of the double intake type. Shaft 6 is supported in bearings 8 of any suitable construction, each carried by a plurality of s'up-' porting plates I3 and I4 resting directly on or attached to a soleplate l1, which in turn rests on. the foundation". Plates l3 and M. are braced by means of cross-plate l9 and cross-plate 2| to which bearings 8 are bolted or otherwise fastened. The supporting structure comprising plates I3, M, l1, l9 and 2| are bolted to the foundation by, means of foundation bolts 31; Supporting plates 13 support directly and are welded to the internal stationary parts of the blower comprising a pair of side plates 24 and a pair of side plates 26 defining the diffuser passage 2'! of the blower which may be reinforced by a pair of stiffening ringsj29 which carry the packing means for the impeller. Side plates 26 are connected with each other by means of stay bolts-3| and are maintainedat the proper spacing by means of spacing collars 32 surrounding. stay bolts 3|. Diffuser passage 21' communicates with the spiral casing 28, of the blower which is directly supported by all of the 4 supporting plates M which are directly welded thereto.

To permit casing 28 to be disassembled such casing is constructed in two halves each provided with fiahgest "which are'bolted together as'is 45,

ally desired to provide the blower with'a confined inlet passage to permit such blower to compress air at pressure differing from atmospheric pressure or at, temperatures differing from the am-' bieht temperature or for compressing gases other the foundation is not illustrated to simplify the than air. The portion of the structure above described then remains unchanged and suitable inlet passages 9 are then defined by means of a plurality of Welded iron plates H, [2 and I4. Such passageways terminate adjacent the inlets of impeller I where the walls of such passage are completed by a semi-cylindrical plate 23. Plates l2 are then preferably sealed against shaft 6 by labyrinth glands supported in sealing plates 34. As will appear from a consideration of Fig. 2 such inlet passage is partially defined by some of the supporting plates 14 and at least one of such supporting plates, such as the center plate l3 represented in Fig. 2, is utilized for guiding the flow of gas through the inlet passage to thereby reduce the losses caused by turbulence in such passage.

It will be understood that, by the use of the construction above described, the weights of the, internal parts comprising plates 24 and 26 and rings 29, of the casing 28, of bearings 8v and of the walls of inlet passage 9 are separately applied to the supporting and guiding plates l3 and I5, and are directly transmitted by such supporting plates to the foundation i 8. Each of the stationary elements of the blower may therefore be designed with the minimum thickness and weight which will permit such element to carry its own weight, without excessive stresses or deformation, both during assembly of the structure and during normal operation thereof. Bracing members between the several portions of the structure are not necessary and the saving of weight thus obtained at least balances the increase in weight due to the addition of the supporting members. Such supporting members provide for guiding the flow of gas or air to avoid turbulence and constitute structural extensions which may be rested directly on the foundation without requiring any of the special precautions which would be required if different portions of the blower were supported by the foundation over separate supporting members.

In the embodiment illustrated in Fig. 3, the

blower is provided with a shaft 38 supported in bearings 8 in a manner similar to that described with respect to the embodiment illustrated in Fig. 1. Shaft 38 is provided with two impeller wheels 39 and M through which the gas to be compressed flows in succession. In the present ance piston 42 mounted on shaft 38.

embodiment the thrust exerted on the shaft as a result of the unequal gas pressures on the sides of impellers 39 and M is preferably compensated by the gas pressure exerted on a bal- Impeller 39 discharges into a diffuser passage 43 leading to a space 46, such space being defined by disk plates 46 and 4'! and a cylindrical plate 48. The gas is led from space M towards impeller 4! through a return passage provided with suitable guide vanes "39 mounted between plate 47 and disk shaped partition 5|. The gas discharged by impeller 41 issues into a second diffuser passage similar to diffuser passage 43, and formed by plates 47 and 56 and is conducted into a spiral casing 54 similar to spiral casing 28 illustrated in Fig. 1. Plates 4E, 41, 5t and 5| are held by means of stay bolts 52 and are maintained in proper spacing by means of spacing collars 53.

Plate 56 has attached thereto a cover 58 for balance piston 52 which cover is provided with suitable sealing means against balance piston 42 and shaft 38. The gas leaking between balance piston 62 and cover 58 may be returned to the inlet passage by means of a bypass 59.

In the present embodiment, diifuser passages 33 and 45 and space 44 are directly supported by means of plates M with which such discharge rings and diffuser are directly connected. Casing 54 is directly connected with some of plates it on the side opposite to the inlet side of the blower. Bearings 8 are directly mounted on plates I 4 as in the embodiment illustrated in Fig. 1. On the inlet side of the blower, some of plates I4 cooperate with plates l3 to define the inlet passage and at least one of such plates serves to guide the flow of gas within passage 9. In the present embodiment, as in the embodiment illustrated in Fig. 1, the weights of the several stationary portions of the blower are thus separately applied to the supporting and guiding members and such stationary portions may be made with the minimum thickness and weight which will support their own weights during;

manufacture and during operation of the blower 26 without excessive stresses or deformations, Ifhe supporting plates may be placed on the founda-. tion without requiring an excessive amount Off care as in the embodiment illustrated in F g. 1,

Although but a few embodiments of the presg5 ent invention have been illustrated and de scribed, it will be apparent to those skilled in the art that various changes and modifications, may be made therein without departing from the spirit of the invention or from the scope of the 30 appended claims.

It is claimed and desired to secure by Letters Patent:

1. In a centrifugal blower arranged to rest directly on a foundation, a plurality of supportin 35 plates resting directly on the foundation, heelings carried only by said supporting plates a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a diffuser passage for said impellers and carried only by said supporting plates, an inlet duct partially formed by said supporting plates, and a discharge casing for said impeller carried only bysaid supporting plates.

3. In a centrifugal blower arranged to rest,

directly on a foundation, a plurality of supporting plates resting directly on the foundation, bearings directly carried only by said supporting plates, a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a diffuser passage for said impellers and directly 0 carried only by said supporting plates, and a. discharge casing for said impeller directly carried by said supporting plates.

4. In acentrifugal blower arranged to rest directly on a foundation, a plurality of support- 65 ing plates resting directly on the foundation, bearings directly carried only by said support ing plates, a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a difiuser passage for said impellers and dl- 7o rectly carried only by said supporting plates, an inlet duct partially formed by said supporting plates, and a discharge casing for said impeller directly carried'only by said supporting plates.

5. Ina centrifugal blower arranged to rest di- 16,

rectly on a foundation, a plurality of supporting plates resting directly on the foundation, bearings carried only by said supporting plates, a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a diffuser passage for said impeller and carried only by said supporting plates, an inlet duct partially defined by said side plates and partly defined by some of said side plates, and a discharge casing for said impeller carried only by said supporting plates.

, 6. In a centrifugal blower arranged to rest directly on a foundation, a plurality of supporting plates resting directly on the foundation, bearings carried only by said supporting plates, a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a diffuser passage for said impeller and carried only by said supporting plates, an inlet duct partially defined by said supporting plates, means including some of said supporting plates for guiding the flow of fluid within said duct, and a discharge casing for said impeller carried only by said supporting plates.

7. In a centrifugal blower arranged to rest directlyon a foundation, a plurality of supporting plates resting directly on the foundation, bearings directly carried only by said supporting plates, a shaft supported in said bearings, an impeller attached to said shaft, side plates forming a diffuser passage for said impeller and directly peller attached to said shaft, side plates forming a diffuser passage for said impeller and directly and only carried by said supporting plates, an inlet duct partially defined by said supporting plates, means including some of said supporting plates for guiding the fiow of fluid Within said duct, and

a discharge casing for said impeller directly and only carried by said supporting plates.

9. In a centrifugal blower arranged to rest directly on a foundation, a pair of supporting plates resting directly on the foundation, bearings carried only by said supporting plates, a shaft supported in said bearings, an impeller attached to said shaft, internal stationary parts partially enclosing said impeller and carried by said supporting plates, and a discharge casing for said impeller carried only by said supporting plates, said internal stationary parts being connected with said discharge casing.

JOHN AVERY.

CERTiFiCATE OF CORRECTIQN.

Patent No. 2,018,827. October 29, 1935.

J OHN AVERY. I

It is hereby certified that error appears in the printed specification of the above numbered patent requiring correction as follows: Page 3, first column, line 8, claim 5, for "side" read supporting; and that the said Letters Patent should be read with this correction therein that the same may conform to the record of the case in the Patent Office.

Signed and sealed this 10th day of December, A. D. 1935.

Leslie Frazer (Seal) Acting Commissioner of Patents. 

